JP3946985B2 - Fluorescence imaging device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fluorescence image capturing apparatus that captures a fluorescence image generated from a measurement target by irradiation with excitation light as an image indicating information related to a living tissue.
[0002]
[Prior art]
Conventionally, when a living tissue is irradiated with excitation light in the excitation light wavelength region of the living body dye, the fluorescence intensity emitted differs between normal tissue and lesion tissue, thereby exciting the living tissue in a predetermined wavelength region. There has been proposed a fluorescence detection apparatus that recognizes the localization and infiltration range of a diseased tissue by irradiating light and detecting fluorescence emitted from a living body dye.
[0003]
Normally, when excitation light is irradiated, strong fluorescence is emitted from normal tissue as shown by a solid line in FIG. 6, and weaker fluorescence is emitted from lesion tissue than fluorescence emitted from normal tissue as shown by a broken line. By measuring the strength, it is possible to determine whether the living tissue is normal or in a lesion state.
[0004]
Furthermore, a method has been proposed in which fluorescence by excitation light is imaged by an imaging device or the like and displayed as a fluorescence image corresponding to the intensity of the fluorescence. And in the said technique, since the biological tissue has an unevenness | corrugation, the intensity | strength of the excitation light irradiated to a biological tissue is not uniform. In addition, the intensity of the fluorescence emitted from the living tissue is substantially proportional to the excitation light illuminance, but the excitation light illuminance decreases in inverse proportion to the square of the distance. For this reason, a lesion tissue located nearer than a normal tissue far from the light source may receive strong fluorescence, and the tissue properties of the living tissue can be accurately identified only by information on the intensity of the fluorescence from the excitation light. I can't. In order to reduce such inconveniences, the ratio of two types of fluorescence intensities obtained from different wavelength bands (narrow band near 480 nm and wide band near 430 nm to 730 nm) is obtained by division, and an operation image based on the division value Display method, that is, an image display method based on the difference in the shape of the fluorescence spectrum that reflects the tissue properties of the living body, or near-infrared light that is uniformly absorbed by various living tissues as the reference light. A method of irradiating the tissue, detecting the intensity of the reflected light reflected by the biological tissue that has been irradiated with the reference light, obtaining a ratio with the fluorescence intensity by division, and displaying an operation image based on the division value, That is, a method for obtaining a value reflecting the fluorescence yield and displaying an image has been proposed. In addition, color information is assigned to a division value of fluorescence intensity in different wavelength bands or a division value of reflected light intensity by irradiation of fluorescence intensity and reference light, and a lesion state of a living tissue is displayed as an image by the difference in color. Furthermore, by synthesizing the color image indicating the lesion state of the biological tissue due to the difference in color and the luminance image obtained by assigning luminance information to the intensity of the reflected light by irradiation of the reference light, There has also been proposed a method for showing an image with a sense of unevenness in which the shape is also reflected in the image.
[0005]
In the above technique, since the fluorescence intensity generated from the living tissue is very weak, the S / N of the fluorescence image based on this fluorescence intensity is very poor. Therefore, as a method for improving the S / N of the fluorescence image, a method for controlling the gain of the multiplication type image sensor based on the intensity of the fluorescence image captured by the image sensor so as to increase the fluorescence intensity. Has been proposed. There has also been proposed a method of actively changing the binning size of the image sensor from the detected fluorescence intensity.
[0006]
[Problems to be solved by the invention]
However, in the method of controlling the gain of the multiplication type image sensor, the noise intensity increases with the fluorescence intensity. Further, in the method of changing the binning size of the image sensor, the fluorescence intensity is increased by binning, but the dark noise of the peripheral pixels is also increased at the time of pixel combination, so that a sufficient S / N cannot be obtained as a result. Furthermore, there is a drawback that the drive circuit of the image sensor for changing the binning size becomes complicated.
[0007]
In view of the above-described problems of the prior art, the present invention provides a fluorescence image capturing apparatus capable of improving the S / N of a fluorescence image based on the fluorescence intensity by increasing only the fluorescence intensity. It is for the purpose.
[0008]
[Means for Solving the Problems]
A first fluorescent imaging apparatus according to the present invention includes an irradiating unit that guides and irradiates excitation light to a measured part, and a fluorescent image based on a fluorescent image generated from the measured part by irradiating excitation light by the irradiating unit. Fluorescence image picked up by an image pickup means in a fluorescent image pickup device comprising an image pickup means for picking up an image with an image pickup device through an imaging optical system and a reading means for reading out an image signal based on a fluorescent image picked up by the image pickup means A magnification for determining the size of the fluorescent image by controlling the magnification of the imaging optical system based on the statistics; It has a control means.
[0009]
Further, the image processing unit may include an image processing unit that performs predetermined image processing on the image signal read by the reading unit, and the image processing unit may perform image processing on the image signal within a predetermined effective range.
[0010]
Further, the image processing apparatus includes a display unit that displays an observation image based on the image signal read by the reading unit, and the display unit displays the observation image based on the image signal in a predetermined effective range that has been image-processed by the image processing unit. Can be displayed.
[0011]
Further, it is possible to have display magnification control means for controlling the display magnification so that the observation image based on the image signal in the predetermined effective range is displayed in a predetermined constant size.
[0012]
Further, the reading means can read only an image signal in a predetermined effective range of the fluorescent image.
[0013]
The second fluorescence imaging apparatus according to the present invention is based on an irradiation unit that guides and irradiates excitation light and illumination light to a measurement target part, and a fluorescence image generated from the measurement target part by irradiation of excitation light by the irradiation unit. An imaging unit that captures a normal image based on a fluorescent image and a normal image reflected from the measurement target by irradiation of illumination light with an imaging device through an imaging optical system, and an image based on the fluorescent image and the normal image captured by the imaging unit A fluorescence image capturing apparatus including a reading unit that reads a signal, the image capturing unit including a statistic calculating unit that calculates a statistic of an image signal of a predetermined region of the fluorescent image captured by the imaging unit, and the imaging unit includes a statistic And a magnification control means for determining the size of the fluorescent image and the normal image by controlling the magnification of the imaging optical system based on the above.
[0014]
In addition, the image processing unit has predetermined image processing that performs predetermined image processing on the image signal read by the reading unit, and the image processing unit generates an image on the image signal of the normal image corresponding to the predetermined effective range and the predetermined effective range. Processing can be performed.
[0015]
In addition, the display unit displays an observation image based on the image signal read by the reading unit, and the display unit is an image signal of a predetermined effective range of the fluorescence image and the normal image processed by the image processing unit. The observation image can be displayed based on the above.
[0016]
Further, it is possible to have display magnification control means for controlling the display magnification so that the observation image based on the image signal in the predetermined effective range is displayed in a predetermined constant size.
[0017]
Further, the reading means can read only the image signals in a predetermined effective range of the fluorescent image and the normal image.
[0018]
A third fluorescence image pickup device according to the present invention is based on an irradiation unit that guides and irradiates excitation light and reference light to a measurement target part, and a fluorescence image generated from the measurement target part by irradiation of excitation light by the irradiation unit. An image pickup means for picking up a reflection image based on a reflection image reflected from a measured part by irradiation of a fluorescence image and a reference light by an image pickup device through an imaging optical system, and an image based on the fluorescence image and the reflection image picked up by the image pickup means A fluorescence image capturing apparatus including a reading unit that reads out a signal, the image capturing unit including a statistic calculating unit that calculates a statistic of an image signal of a predetermined region of the fluorescent image or the reflected image captured by the imaging unit; And a magnification control means for determining the size of the fluorescent image and the reflected image by controlling the magnification of the imaging optical system based on the statistic.
[0019]
In addition, the image processing unit that performs predetermined image processing on the image signal read by the reading unit, the image processing unit performs image processing on the image signal of the reflection image corresponding to the predetermined effective range and the predetermined effective range. Can be applied.
[0020]
In addition, the display unit displays an observation image based on the image signal read by the reading unit, and the display unit is an image signal of a predetermined effective range of the fluorescent image and the reflection image that are image-processed by the image processing unit. The observation image can be displayed based on the above.
[0021]
Further, it is possible to have display magnification control means for controlling the display magnification so that the observation image based on the image signal in the predetermined effective range is displayed in a predetermined constant size.
[0022]
Further, the reading means can read only image signals in a predetermined effective range of the fluorescent image and the reflected image.
[0023]
A fourth fluorescence image pickup apparatus according to the present invention is configured to irradiate excitation light, reference light, and illumination light by directing them to the measurement target portion and irradiate the fluorescence, and generate fluorescence from the measurement target portion by irradiating the excitation light by the irradiation means Fluorescence image based on image, reflected image based on reflected image reflected from measured part by irradiation of reference light, and normal image based on normal image reflected from measured part by irradiation of illumination light through imaging optical system Fluorescence image or reflection imaged by imaging means in a fluorescence imaging apparatus comprising imaging means for imaging by an element and reading means for reading out an image signal based on a fluorescent image, a reflected image and a normal image taken by the imaging means A statistic calculating unit that calculates a statistic of an image signal of a predetermined region of the image, and the imaging unit controls the magnification of the imaging optical system based on the statistic; Image, is characterized in that it has a magnification control means for determining the magnitude of the reflected image and a normal image.
[0024]
In addition, the image processing means includes an image processing means for performing predetermined image processing on the image signal read by the reading means, and the image processing means includes an image signal of a reflection image and a normal image corresponding to the predetermined effective range and the predetermined effective range Apply image processing to
Can be.
[0025]
In addition, the display unit displays an observation image based on the image signal read by the reading unit, and the display unit has a predetermined effective range of the fluorescent image, the reflection image, and the normal image that are image-processed by the image processing unit. The observation image can be displayed based on the image signal.
[0026]
Further, it is possible to have display magnification control means for controlling the display magnification so that the observation image based on the image signal in the predetermined effective range is displayed in a predetermined constant size.
[0027]
Further, the reading means may read only image signals within a predetermined effective range of the fluorescent image, the reflected image, and the normal image.
[0028]
Here, in the first to fourth fluorescent image capturing apparatuses, the above-mentioned “controlling the magnification of the imaging optical system based on the statistical amount” means, for example, the statistical amount of the image signal of a predetermined region of the fluorescent image. Is smaller than a predetermined threshold value, that is, when the magnitude of the image signal of the fluorescent image is not sufficiently large, the magnification is controlled by the imaging optical system so that the size of the fluorescent image is reduced. When it is larger than the predetermined threshold, that is, when the image signal of the fluorescent image is large, the magnification is controlled so that the size of the fluorescent image is enlarged by the imaging optical system, and the statistic is set to a substantially desired value. In some cases, that is, when the size of the image signal of the fluorescent image is an appropriate size, it means that the magnification is controlled so that the size of the fluorescent image is equalized by the imaging optical system. Alternatively, a plurality of threshold values and magnifications corresponding to the threshold values may be set, and the magnifications may be changed step by step. The “size of the fluorescent image” means the size of the fluorescent image formed on the image sensor.
[0029]
The “statistics based on the image signal” refers to, for example, the image intensity of the fluorescent image or the reflected image (meaning the image signal itself), the Y signal converted at the time of display (YIQ Y of NTSC signal, This means a statistic calculated from Y or the like of YCbCr). When luminance information is assigned to the image signal of the reflected image, a statistic may be calculated from the luminance information. In short, any statistic calculated from a signal or information based on an image signal of a fluorescent image or a reflected image may be used.
[0030]
In the second fluorescence imaging apparatus, the size of the normal image can be controlled in accordance with the size of the fluorescence image. For example, the fluorescence image is reduced and magnified by the imaging optical system as described above. The normal image can be enlarged at the same magnification, and the normal image can be enlarged when the fluorescent image is enlarged by the imaging optical system.
[0031]
Further, in the third fluorescence imaging apparatus, the size of the reflected image can be controlled according to the size of the fluorescence image. For example, when the fluorescence image is reduced by the imaging optical system as described above, The reflected image can be reduced, the reflected image can be enlarged when the fluorescent image is magnified, and the reflected image can be enlarged when the fluorescent image is magnified.
[0032]
Further, in the fourth fluorescent image capturing apparatus, the sizes of the normal image and the reflected image can be controlled according to the size of the fluorescent image. For example, the fluorescent image is reduced by the imaging optical system as described above. If the fluorescent image is magnified, the normal image and the reflected image are also magnified.If the fluorescent image is magnified, the normal image and the reflected image are magnified. The image can also be enlarged.
[0033]
In the first or second fluorescent image capturing apparatus, the predetermined region may be the entire fluorescent image, and the statistic calculating unit may calculate the statistic of the image signal of the entire fluorescent image. .
[0034]
In the third or fourth fluorescent image capturing apparatus, the predetermined region is the entire fluorescent image or the entire reflected image, and the statistic calculating means calculates the statistic of the image signal of the entire fluorescent image or the entire reflected image. It can be calculated.
[0035]
In the first or second fluorescence imaging apparatus, the predetermined region is a region of interest of the fluorescence image, and the statistic calculation means calculates a statistic of the image signal of the region of interest. it can.
[0036]
Further, in the third or fourth fluorescent image capturing apparatus, the predetermined region is a region of interest of the fluorescent image or the reflected image, and the statistic calculating means calculates a statistic of the image signal of the region of interest. can do.
[0037]
Here, the above-mentioned “region of interest” means, for example, a region having a particularly high degree of interest for diagnosis in image diagnosis.
[0038]
The “predetermined effective range” is, for example, a range in which an observation target is actually imaged on an image sensor, and is desired to be displayed as an image in a captured fluorescent image in image diagnosis. It means a range.
[0039]
In the first to fourth fluorescent image capturing apparatuses, the statistic calculating means performs an operation of weighting a predetermined range in the predetermined area according to the degree of interest, and calculates the statistics of the calculated image signal. The amount can be calculated.
[0040]
Here, “calculate weighting according to the degree of interest in the predetermined range in the predetermined area” means, for example, multiplying the image signal in the range of highest interest by 1 in the predetermined area. This means that the image signal of the region with the highest interest level is multiplied by 0.5, and the image signal of the remaining region is multiplied by 0.1 to perform weighting according to the interest level.
[0041]
In the first to fourth fluorescent image capturing apparatuses, the statistical amount of the image signal includes the maximum value, the minimum value, the average value, the combination of the maximum value and the standard deviation, the combination of the minimum value and the standard deviation, and the average value. It is at least one of the combinations of standard deviations, and when any of the maximum value, the minimum value, and the average value of the statistic is small, the magnification can be reduced, and when it is large, the magnification can be increased.
[0042]
In the first to fourth fluorescent image capturing apparatuses, the reading unit may control the reading frequency according to a predetermined effective range.
[0043]
Here, “controlling the readout frequency according to the predetermined effective range” means, for example, that when the image picked up by the CCD is read out as an image signal by the reading means, the reading means is based on a reference clock signal. The image signal is sequentially read out by the horizontal / vertical transfer signal. However, the wider the predetermined effective range, the larger the number of pixels from which the image signal is read out, and the higher the read frequency. Therefore, the readout frequency is determined according to the width of the effective range, and the readout means sequentially reads out the image signal by the horizontal / vertical transfer signal in accordance with the readout frequency.
[0044]
In the first to fourth fluorescent imaging devices, when the pixel data based on the image signal is indicated by the number of bits of 9 bits or more, the bit is bit-shifted so that the data is indicated by the number of bits of the upper 8 bits or less. A statistic calculation unit may include a shift unit, and the statistic calculation unit may calculate the statistic based on the bit-shifted pixel data.
[0045]
In addition, the first to fourth fluorescent image capturing devices may be in the form of an endoscope in which a part or all of the irradiation unit, the imaging unit, and the reading unit have an insertion portion that is inserted into the living body. .
[0046]
In the first to fourth fluorescent image capturing apparatuses, a part of the irradiation unit, the imaging unit, and the reading unit is disposed in the insertion unit, and the irradiation unit, the imaging unit, and the part other than the portion disposed in the insertion unit, A part of the reading unit may be arranged in the processor unit, and the imaging optical system whose magnification is controlled by the magnification control unit may be arranged in the processor unit.
[0047]
In the first to fourth fluorescent image capturing apparatuses, a part of the irradiation unit, the imaging unit, and the reading unit is disposed in the insertion unit, and the irradiation unit, the imaging unit, and the part other than the portion disposed in the insertion unit, A part of the reading unit may be disposed in the processor unit, and the imaging optical system controlled by the magnification control unit may be disposed in the insertion unit.
[0048]
【The invention's effect】
According to the first fluorescence image capturing apparatus of the present invention, the statistic calculating unit calculates the statistic of the image signal of the predetermined region of the fluorescent image captured by the imaging unit, and the magnification control unit is based on the statistic. Since the size of the fluorescent image is determined by controlling the magnification of the imaging optical system, even when the intensity of the fluorescent image is weak, that is, when the magnitude of the image signal of the fluorescent image is smaller than the desired value However, the imaging magnification system is controlled to an appropriate magnification based on the statistic and only the intensity of the fluorescent image is increased by reducing the fluorescent image, so the S / N of the fluorescent image can be improved.
[0049]
According to the second fluorescence image capturing apparatus of the present invention, the statistic calculating unit calculates the statistic of the image signal of the predetermined region of the fluorescent image captured by the imaging unit, and the magnification control unit is based on the statistic. Since the sizes of the fluorescence image and the normal image are determined by controlling the magnification of the imaging optical system, the size of the normal image is set to the size of the fluorescence image in addition to the effect of the first fluorescence image capturing apparatus. It can be according to the size.
[0050]
In the third fluorescence image capturing apparatus according to the present invention, the statistic calculating unit calculates the statistic of the image signal of the predetermined region of the fluorescent image or the reflected image captured by the imaging unit, and the magnification control unit is based on the statistic. Since the sizes of the fluorescent image and the reflected image are determined by controlling the magnification of the imaging optical system, the reflected image is made the size of the fluorescent image in addition to the effect of the first fluorescent image capturing apparatus. The size can be made suitable, and even when image calculation is performed using a fluorescent image and a reflection image, appropriate inter-image calculation processing can be performed. Furthermore, when the statistic calculation means calculates the statistic of the image signal of the predetermined area of the reflected image, the magnification can be controlled to reflect more the distance between the imaging means and the part to be measured.
[0051]
In the fourth fluorescence image capturing apparatus according to the present invention, the statistic calculating unit calculates the statistic of the image signal of the predetermined region of the fluorescent image or the reflected image captured by the imaging unit, and the magnification control unit is based on the statistic. Since the sizes of the fluorescent image, the reflected image, and the normal image are determined by controlling the magnification of the imaging optical system, the same effects as those of the first to third fluorescent image capturing apparatuses can be obtained. it can.
[0052]
In the first to fourth fluorescent image capturing apparatuses, when the image processing means performs image processing on an image signal in a predetermined effective range within a predetermined area, the image processing time is shortened. be able to.
[0053]
In the first to fourth fluorescent image capturing devices, particularly when the display means displays an observation image based on an image signal in a predetermined effective range image-processed by the image processing means. Only a range with a high degree of interest can be displayed as an observation image.
[0054]
In the first to fourth fluorescent imaging devices, when the display magnification is controlled so that an observation image based on an image signal in a predetermined effective range is displayed at a predetermined constant size, Even if the image is reduced by the imaging optical system, the visibility can be ensured by the enlarged display.
[0055]
In the first to fourth fluorescent image capturing apparatuses, when the reading unit reads only an image signal in a predetermined effective range, the reading process time can be shortened.
[0056]
Further, in the first or second fluorescent image capturing apparatus, when the predetermined region is the entire fluorescent image, and the statistic calculating unit calculates the statistic of the image signal of the entire fluorescent image, A more appropriate statistic that reflects the entire fluorescence image can be calculated.
[0057]
In the third or fourth fluorescent image capturing apparatus, the predetermined region is the entire fluorescent image or the entire reflected image, and the statistic calculating means calculates the statistic of the image signal of the entire fluorescent image or the reflected image. In this case, it is possible to calculate a more appropriate statistic reflecting the entire fluorescent image or the entire reflected image. In particular, when calculating the statistic of the image signal of the entire reflected image, the imaging means A statistic that more reflects the distance to the measurement unit can be calculated.
[0058]
Further, in the first or second fluorescence imaging apparatus, when the predetermined region is a region of interest of the fluorescence image, and the statistic calculation unit calculates the statistic of the image signal of the region of interest. More appropriate statistics can be calculated for the region of interest.
[0059]
Further, in the third or fourth fluorescent image capturing device, the predetermined region is a region of interest of the fluorescent image or the reflected image, and the statistic calculating unit calculates a statistic of the image signal of the region of interest. In this case, a more appropriate statistic can be calculated for the region of interest. Especially when the statistic of the image signal of the entire reflected image is calculated, the statistic that more reflects the distance between the imaging means and the part to be measured. The amount can be calculated.
[0060]
Further, in the first to fourth fluorescent image capturing apparatuses, the statistic calculation means performs a calculation for weighting a predetermined range in the predetermined area according to the degree of interest, and calculates the statistics of the calculated image signal. When the amount is calculated, an image signal in a range of higher interest in the fluorescent image or the reflected image can be reflected in the statistic.
[0061]
Further, in the first to fourth fluorescent image capturing apparatuses, the statistic of the image signal includes a maximum value, a minimum value, an average value, a combination of the maximum value and a standard deviation, a combination of a minimum value and a standard deviation, and an average value. When at least one of the combinations of standard deviations, when the maximum value, the minimum value, or the average value of the statistic is small, the magnification is reduced, and when it is large, the magnification is increased. A statistic can be calculated by a simple calculation, and a magnification control reflecting the statistic can be performed.
[0062]
In the first to fourth fluorescent image capturing apparatuses, when the reading unit controls the reading frequency according to a predetermined effective range, the reading frequency can be limited to the minimum necessary. Therefore, it is possible to limit the readout noise generated with the readout, and to improve the S / N of the fluorescence image, the reflection image, and the normal image.
[0063]
In the first to fourth fluorescent imaging devices, when the pixel data based on the image signal is indicated by the number of bits of 9 bits or more, the bit is bit-shifted so that the data is indicated by the number of bits of the upper 8 bits or less. If the statistic calculation means includes a shift means and calculates the statistic based on the bit-shifted pixel data, an 8-bit general-purpose statistical calculator can be used to speed up the calculation process. Can be achieved.
[0064]
In the case where the first to fourth fluorescent image capturing devices are in the form of an endoscope in which a part or all of the irradiation unit, the imaging unit, and the reading unit have an insertion portion inserted into the living body. It can be effectively used as a fluorescence endoscope apparatus.
[0065]
Further, in the first to fourth fluorescent image capturing apparatuses, a part of the irradiation unit, the imaging unit, and the reading unit is disposed in the insertion unit, and the irradiation unit, the imaging unit, and the part other than the portion disposed in the insertion unit, When a part of the reading unit is arranged in the processor unit and the imaging optical system whose magnification is controlled by the magnification control unit is arranged in the processor unit, the configuration of the insertion unit Can be simplified, and the weight of the insertion portion is reduced, so that the operability can be improved.
[0066]
Further, in the first to fourth fluorescent image capturing apparatuses, a part of the irradiation unit, the imaging unit, and the reading unit is disposed in the insertion unit, and the irradiation unit, the imaging unit, and the part other than the portion disposed in the insertion unit, When a part of the reading unit is disposed in the processor unit and the imaging optical system controlled by the magnification control unit is disposed in the insertion unit, the apparatus is configured to be smaller. be able to.
[0067]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments in which a fluorescence imaging apparatus of the present invention is applied to a fluorescence endoscope will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a fluorescence endoscope according to the present embodiment.
[0068]
The fluorescence endoscope according to the present embodiment includes an endoscope insertion unit 100 that is inserted into a site suspected of being a patient's lesion, an image signal processing unit 1 that processes information obtained from a living tissue into an image signal, The monitor 600 displays a signal processed by the image signal processing unit 1 as a visible image. The image signal processing unit 1 includes an illumination unit 110 including two light sources that respectively emit white light Lw for normal images and excitation light Lr for autofluorescence images, and autofluorescence generated from the living tissue 9 by irradiation of the excitation light. An image detection unit 300 that picks up an image Zj, converts it into a digital value and outputs it as image data, and outputs the image data of the autofluorescence image output from the image detection unit 300 by performing arithmetic operations such as distance correction and image processing. An image calculation unit 400 that converts a normal image into a digital value as image data, converts the image data and an output signal of the image calculation unit 400 into a video signal, and outputs a video signal. And a foot switch 2 for switching the state and the composite image display state.
[0069]
The endoscope insertion portion 100 includes a light guide 101 that extends to the tip inside and an image fiber 102. An illumination lens 103 is provided at the distal end portion of the light guide 101, that is, the distal end portion of the endoscope insertion portion 100. Further, the image fiber 102 is a multi-component glass fiber, and includes an excitation light filter 104 and a condensing lens 105 at the tip thereof. In the light guide 101, a white light guide 101a and an excitation light guide 101b are bundled and integrated in a cable shape, and the white light guide 101a and the excitation light guide 101b are connected to the illumination unit 110. One end of the image fiber 102 is connected to the image detection unit 300.
[0070]
The illumination unit 110 includes a GaN-based semiconductor laser 111 that emits excitation light Lr for self-fluorescent images, a semiconductor laser power source 112 that is electrically connected to the GaN-based semiconductor laser 111, and white that emits white light Lw for normal images. The light source 114 includes a white light power source 115 electrically connected to the white light source 114.
[0071]
The image fiber 102 is connected to the image detection unit 300, and the self-fluorescent image propagated through the image fiber 102, the collimating lens 301 that forms a normal image, and the normal image that has passed through the collimating lens 301 are totally reflected in the perpendicular direction. The fluorescent image transmitted through the collimating lens 301 transmits 50% of the light quantity of the movable mirror 302 that moves to and passes through the position indicated by the broken line, and the autofluorescent image (light having a wavelength of 750 nm or less) transmitted through the collimating lens 301, and 50 % Mirror 303 reflecting right-angled direction, self-fluorescent image mirror 304 reflecting the half-mirror 303 reflected perpendicularly, fluorescent image mirror 304 reflecting right-angled direction, and the magnification controlled by magnification control means 316 described later and the self-transmitted through the half mirror 303 Magnify or reduce the fluorescence image and the autofluorescence image reflected from the fluorescence image mirror 304 Alternatively, the imaging optical system 305 that transmits at the same magnification, the broadband fluorescent image condensing lens 306 and the narrow-band fluorescent image condensing lens 307 that form an autofluorescent image transmitted through the imaging optical system 305 at a predetermined magnification. Wideband bandpass filter 308 for selecting a wavelength of 430 nm to 730 nm from the autofluorescent image transmitted through the broadband fluorescent image condensing lens 306, and high sensitivity for the broadband fluorescent image for capturing the autofluorescent image transmitted through the broadband bandpass filter 308 The self-fluorescent image which permeate | transmitted the narrow-band band pass filter 309 and the narrow-band band pass filter 309 which take out the wavelength of 430 nm-530 nm from the self-fluorescent image imaged by the image pick-up element 310 and the condensing lens 307 for narrow-band fluorescent images is imaged. Based on a control signal from a high-sensitivity imaging device 311 for narrow-band fluorescence image and a magnification control means 316 described later. Based on the control signals from the reading means 314 and the reading means 314 for controlling the driving ranges in the high-sensitivity imaging device 310 for the broadband fluorescent image and the high-sensitivity imaging device 311 for the narrow-band fluorescent image and reading out the image signal in the driving range. An AD converter 312 that converts the image signal output from the high-sensitivity image sensor 310 for the broadband fluorescent image into a digital value and outputs it as image data; An AD converter 313 that converts an image signal output from the element 311 into a digital value and outputs it as image data, an image data output from the AD converter 312 and stored in a broadband fluorescent image memory 401 described later, and the AD converter Statistics based on image data output from 313 and stored in a narrowband fluorescent image memory 402 described later Statistic calculating means 315 for calculating the image forming magnification system 305 and the magnification of the image forming magnification system 305 and a normal image forming optical system 507 (to be described later) based on the statistic output from the statistic calculating means 315 to determine the image forming optical system 305 and A magnification control signal is output so that the magnification of the normal image imaging optical system 507 becomes the magnification, and the high-sensitivity image sensor 310 for the broadband fluorescent image, the high-sensitivity image sensor 311 for the narrow-band fluorescence image, and A magnification control means 316 is provided for outputting a control signal to the reading means 314 and 508 so as to determine a drive range in a normal image pickup element 503, which will be described later, and read out an image signal in the drive range.
[0072]
Note that the statistic calculation unit 315 includes a bit shift unit 317 that shifts the number of bits of the image data to 8 bits or less when calculating the statistic.
[0073]
The image calculation unit 400 stores the broadband fluorescent image memory 401 that stores the image data of the broadband autofluorescence image output from the AD converter 312, and the image data of the narrowband autofluorescence image output from the AD converter 313. Each corresponding pixel value of the image data of the broadband autofluorescence image stored in the memory for narrowband fluorescence image 402 and the memory for broadband fluorescence image 401 and the image data of the broadband autofluorescence image stored in the memory for narrowband fluorescence image 402 An image generation unit 403 that calculates a calculated value of each pixel by performing a calculation according to the ratio of the image, assigns color information according to the size of the calculated value, and generates and outputs a color image.
[0074]
The display signal processing unit 500 enlarges the normal image reflected by the normal image mirror 501 with the magnification controlled by the normal image mirror 501 that reflects the normal image reflected by the movable mirror 302 in the right-angle direction and the magnification control means 316. Or, a normal image focusing optical system 507 that transmits at the same magnification, a normal image condensing lens 502 that forms an enlarged or equal magnification normal image by the normal image imaging optical system 507, and a normal image condensing lens 502. The normal image pickup element 503 for picking up the normal image formed in step S3, and the readout of the image signal in the drive range by controlling the drive range in the normal image pickup element 503 based on the control signal from the magnification control means 316 Based on the control signal from the means 508 and the reading means 508, the image signal output from the normal image pickup device 503 is converted into a digital value to obtain image data. Output AD converter 504, normal image memory 505 for storing digitized image signals, image signals output from normal image memory 505, and color image signals output from image generation means 403 as video signals A video signal processing circuit 506 for converting and outputting is provided. The monitor 600 switches between a normal image and a color image for display.
[0075]
Next, the operation of the fluorescence endoscope in the above embodiment will be described. First, the operation when displaying a color image using autofluorescence images in two different wavelength bands will be described.
[0076]
Based on a signal from the control computer 200, the semiconductor laser power source 112 drives the pump light Lr from the GaN-based semiconductor laser 111. The pump light Lr passes through the pump light condensing lens 113, and the pump light guide. After being incident on 101 b and guided to the distal end portion of the endoscope insertion portion 100, the living tissue 9 is irradiated from the illumination lens 103. The autofluorescence image from the living tissue 9 generated by the irradiation of the excitation light Lr is collected by the condenser lens 105, passes through the excitation light cut filter 104, enters the tip of the image fiber 102, passes through the image fiber 102, The light enters the collimating lens 301. The excitation light cut filter 104 is a long pass filter that transmits all fluorescence having a wavelength of 420 nm or more. Since the wavelength of the excitation light Lr is 410 nm, the excitation light reflected by the living tissue 9 is cut by the excitation light cut filter 104. The autofluorescence image transmitted through the collimator lens 301 is transmitted by the half mirror 303 with a transmittance of 50% and reflected with a reflectance of 50%. The autofluorescence image reflected by the half mirror 303 in the right angle direction reflects the fluorescence image mirror 304 in the right angle direction. Both the autofluorescence image transmitted through the half mirror 303 and the autofluorescence image reflected from the fluorescence image mirror 304 are incident on the imaging optical system 305. At this time, the autofluorescence image first incident on the imaging optical system 305 passes through the imaging optical system 305 at the same magnification. The autofluorescence image transmitted through the imaging optical system 305 at the same magnification is formed by the broadband fluorescent image condensing lens 306, and the autofluorescence image transmitted through the broadband fluorescent image condensing lens 306 is converted into the broadband bandpass filter 308. And is captured by the high-sensitivity image sensor 310 for a broadband fluorescent image. The autofluorescence image reflected by the fluorescence image mirror 304 is formed by the narrowband fluorescence condenser lens 307, passes through the narrowband bandpass filter 309, and is captured by the narrowband fluorescence image high-sensitivity image sensor 311. Is done.
[0077]
The self-fluorescent images captured by the broadband fluorescent image high-sensitivity image sensor 310 and the narrow-band fluorescent image high-sensitivity image sensor 311 are converted into image signals that are electrical signals, and the image signals are read out by the control signals of the reading means 314, respectively. It is. The image signal output from the broadband fluorescent image high-sensitivity image sensor 310 is input to the AD converter 312, digitized, and then stored in the broadband fluorescent image memory 401, and the narrow-band fluorescent image high-sensitivity image sensor. The image signal output from 311 is input to the AD converter 313, digitized, and stored in the narrowband fluorescent image memory 402.
[0078]
Here, after the first self-fluorescence image is captured and stored in the broadband fluorescent image memory 401 and the narrowband fluorescent image memory 402, the image data of the region of interest among the image data is output to the statistic calculation means 315. The For example, when the area of the image data stored in the broadband fluorescent image memory 401 and the narrowband fluorescent image memory 402 is the area 60 shown in FIG. 3, the image data of the area 61 that is the area of interest is output. The region of interest may be a preset region or a region input by a predetermined input means (not shown). Further, the image data of the region of interest 61 output to the statistic calculation unit 315 is bit-shifted to 8 bits or less by the bit shift unit 317, and then the statistic calculation unit 315 performs an operation for weighting according to the interest level. Is called. For example, if the region of highest interest in the region of interest 61 is the region 63, this image signal is multiplied by 1, and if the region of highest interest is the region 62 excluding the region 63, 0. If the region with the highest degree of interest is the region 61 excluding the region 62, the image data is multiplied by 0.1. Then, an average value is taken for all weighted image data in the region 61. This average value is output to the magnification control means 316, and the magnification control means 316 determines the magnification of the autofluorescence image and the normal image according to this average value, and the imaging optical system 305 and the normal image imaging optics are set to this magnification. A magnification control signal is output to the system 507. It is assumed that an appropriate magnification of the imaging optical system 305 and the normal image imaging optical system 507 corresponding to the average value output from the statistic calculation unit 315 is set in the magnification control unit 316. For example, when the average value is smaller than a desired value, that is, when the size of the autofluorescence image signal is not sufficiently large, the magnification of the autofluorescence image is set by the imaging optical system 305. When the average value is larger than a desired value, that is, when the size of the autofluorescence image signal is large, the size of the autofluorescence image is enlarged by the imaging optical system 305. Further, when the average value is a substantially desired value, that is, when the autofluorescence image signal is appropriate, the magnification at which the size of the autofluorescence image is multiplied by the imaging optical system 305 It is.
[0079]
Then, the next autofluorescence image is taken through the imaging optical system 305 controlled to an appropriate magnification by the magnification control signal of the magnification control means 316. Further, a driving range corresponding to the effective range is output from the magnification control unit 316 to the reading unit 314, and the reading unit 314 has a high-sensitivity image sensor 311 for narrowband fluorescent images and a broadband fluorescent image within the driving range corresponding to the effective range. The image data of the high-sensitivity image sensor 310 is read out. The effective range is an area to be displayed as an image, and may be set in advance or input by a predetermined input means (not shown). Further, when the narrow-band fluorescent image high-sensitivity image sensor 311 and the wide-band fluorescent image high-sensitivity image sensor 310 are, for example, a CCD, the reading unit 314 performs reading using the horizontal / vertical synchronization signal and the reference clock signal. The drive range is controlled according to the effective range by changing the horizontal / vertical synchronization signal and the reference clock frequency. When a reduced autofluorescence image is picked up by the imaging optical system 305, the readout frequency is lowered, so that the readout noise of the CCD can be reduced.
[0080]
The image data of the driving range corresponding to the effective range read by the reading unit 314 is stored in the narrowband fluorescent image memory 318 and the broadband fluorescent image memory 319.
[0081]
Then, the narrow-band autofluorescence image in the effective range stored in the narrow-band fluorescence image memory 318 and the wide-band autofluorescence image in the effective range stored in the wide-band fluorescence image memory 319 are converted into corresponding Calculation is performed according to the ratio of each pixel value of the image, color information is assigned to the calculated value, and an image signal having the color information is generated and output. The color image generated by the image generation unit 403 is input to the monitor 600 after DA conversion by the video signal processing circuit 506, and the color image in the effective range is displayed. It is possible to determine whether the tissue is a normal tissue or a diseased tissue based on the difference in color of the color images.
[0082]
Next, the operation when displaying a normal image will be described. First, the white light source 115 is driven based on a signal from the control computer 200, and the white light Lw is emitted from the white light source 114. The white light Lw is incident on the white light guide 101a via the white light condensing lens 116. After being guided to the distal end portion of the endoscope insertion portion 100, the living tissue 9 is irradiated from the illumination lens 103. The reflected light of the white light Lw is collected by the condenser lens 105, passes through the excitation light filter 104, enters the tip of the image fiber 102, enters the collimator lens 301 through the image fiber 102. The reflected light that has passed through the collimator lens 301 is reflected by the movable mirror 302 and the normal image mirror 501 and enters the normal image imaging optical system 507. At this time, the magnification of the normal image forming optical system 507 is controlled in accordance with the magnification control signal output from the magnification control means 316. For example, when the magnification is controlled so that the autofluorescence image is enlarged in the imaging optical system 305, the normal image imaging optical system 507 is also controlled to the same magnification, and the normal image is enlarged. The Further, when the magnification is controlled so that the autofluorescence image is reduced or reduced by the imaging optical system 305, the normal image imaging optical system 507 transmits the normal image by controlling the magnification to the same magnification. The normal image controlled to an appropriate magnification by the normal image imaging optical system 507 is incident on the normal image condensing lens 502. The normal image transmitted through the normal image condensing lens 502 is formed on the normal image pickup element 503. Here, the normal image pickup element 503 is controlled by the reading unit 508 so that image data corresponding to the effective range in the autofluorescence image is read. The effective range image data output from the normal image pickup device 503 is input to the AD converter 504, digitized, and stored in the normal image memory 505. The image signal in the effective range stored in the normal image memory 505 is input to the monitor 600 after DA conversion by the video signal processing circuit 506 and displayed on the monitor 600 as a visible image. Note that the signal processing in the video signal processing circuit 506 may be a frame sequential method or a homogeneous equation.
[0083]
A series of operations related to the color image display operation and the normal image display operation are controlled by the control computer 200. The color image display state and the normal image display state are switched by pressing the foot switch 2.
[0084]
According to the fluorescence endoscope to which the fluorescence imaging apparatus according to the present invention is applied, the statistic calculating unit 315 calculates the statistic of the image signal of the predetermined region of the fluorescent image, and the magnification control unit 316 is based on the statistic. Since the size of the fluorescent image is determined by controlling the magnification of the imaging optical system 305, even when the intensity of the fluorescent image is weak, that is, the size of the image signal of the fluorescent image is smaller than a desired value. Even in this case, since the imaging magnification system is controlled to an appropriate magnification based on the statistics and only the intensity of the fluorescent image is increased by reducing the fluorescent image, the S / N of the fluorescent image can be improved. .
[0085]
In addition, since the image calculation unit 400 performs image processing on an image signal in a predetermined effective range within a predetermined region, the image processing time can be shortened.
[0086]
In addition, since the monitor 600 displays the observation image based on the image signal in the predetermined effective range image-processed by the image calculation unit 400, only the range having a particularly high degree of interest is displayed as the observation image. Can do. At this time, if the size of the observation image displayed on the monitor 600 is also changed according to the magnification controlled by the magnification control means 316 (for example, when the autofluorescence image is reduced by the magnification control means 316). Reduces the mosaic of the observation image due to the reduction in the number of pixels.
[0087]
In addition, since the reading unit 314 reads only the image signal within a predetermined effective range, the time for the reading process can be shortened.
[0088]
Further, since the reading means 314 controls the reading frequency in accordance with a predetermined effective range, the reading frequency can be limited to the minimum necessary, so that reading noise generated during reading is limited. S / N of the fluorescence image, the reflection image, and the normal image can be improved.
[0089]
Further, since the statistic calculation unit 317 calculates the statistic based on the pixel data bit-shifted to 8 bits or less by the bit shift unit 317, an 8-bit general-purpose statistical calculator can be used. It is possible to speed up the arithmetic processing.
[0090]
Next, an embodiment in which the second fluorescence imaging apparatus of the present invention is applied to a fluorescence endoscope will be described with reference to the drawings. FIG. 2 is a schematic configuration diagram of the fluorescence endoscope of the present embodiment. In addition, the said 1st Embodiment uses the same number about an equivalent element, and abbreviate | omits description unless there is particular need.
[0091]
The fluorescence endoscope according to the present embodiment includes an endoscope insertion unit 150 that is inserted into a site suspected of being a patient's lesion, an image signal processing unit 3 that processes information obtained from biological tissue into an image signal, The monitor 600 displays a signal processed by the image signal processing unit 3 as a visible image. The image signal processing unit 3 includes an illumination unit 150 including three light sources that respectively emit white light Lw for normal images, excitation light Lr for autofluorescence images, and reference light Ls for reference images, and a living body by irradiation with the excitation light. An image detection unit 350 that captures an autofluorescence image Zj generated from the tissue 9 and a reflection image Zs generated from the living tissue 9 by irradiation with reference light, converts the digital image into digital values, and outputs the image data, and an image detection unit 350 From the image data of the autofluorescence image output from the image, performs distance correction and the like, assigns color information to the calculated value, assigns luminance information to the image data of the reflected image, and synthesizes and outputs the two pieces of image information The image calculation unit 450 that converts the normal image into a digital value to obtain image data, and the image data and the output signal of the image calculation unit 450 are converted into a video signal. A display signal processing unit 500 for converting and outputting the composed of foot switch 2 which for switching between the normal image display state a composite image display state.
[0092]
The endoscope insertion section 150 includes a light guide 151 that extends to the tip inside and an image fiber 152. An illumination lens 153 is provided at the distal end of the light guide 151, that is, at the distal end of the endoscope insertion portion 150. The image fiber 152 is a multi-component glass fiber, and includes an excitation light filter 154 and a condensing lens 155 at the tip thereof. The light guide 151 is a bundle of a white light guide 151a, an excitation light guide 151b, and a reference light guide 151c, and is integrated in a cable shape. The white light guide 151a, the excitation light guide 151b, and the reference light The guide 151c is connected to the lighting unit 110. One end of the image fiber 152 is connected to the image detection unit 350.
[0093]
The illumination unit 150 includes a GaN-based semiconductor laser 111 that emits excitation light Lr for autofluorescence images, a semiconductor laser power source 112 that is electrically connected to the GaN-based semiconductor laser 111, and a white light that emits white light Lw for normal images. A light source 114, a white light source 115 electrically connected to the white light source 114, a reference light source 117 that emits reference light Ls for reflected images, and a reference light source 118 that is electrically connected to the reference light source 117. I have.
[0094]
An image fiber 152 is connected to the image detection unit 350, and a collimating lens 351 that forms an autofluorescence image, a normal image, and a reflected image propagated through the image fiber 152, and a normal image that has passed through the collimating lens 351 is perpendicular to the image detection unit 350. The self-fluorescent image and the reflected image that have been totally reflected and transmitted through the collimating lens 351 are moved to the position indicated by the broken line 352, and the movable mirror 352 that passes through the collimating lens 351. The dichroic mirror 353 that transmits the reflected image transmitted through the collimator lens 351, and the half mirror that transmits 50% of the light quantity of the autofluorescent image reflected in the right angle direction and reflects 50% in the right angle direction. 354, autofluorescence image transmitted through half mirror 354 at right angle Narrow-band fluorescent image mirror 355 reflecting in the direction, reflected image transmitted through dichroic mirror 353 with magnification controlled by magnification control means 369 described later, autofluorescent image reflected in half-angle direction at half mirror 354, and transmitted through half mirror 354 The auto-fluorescent image reflected by the narrow-band fluorescent image mirror 355 is enlarged, reduced, or equalized and transmitted through the imaging optical system 356, and the auto-fluorescent image and the reflected image transmitted through the imaging optical system 356 at a predetermined magnification. A wavelength of 430 nm to 730 nm from the self-fluorescent image transmitted through the broadband fluorescent image condensing lens 358, the narrow band fluorescent image condensing lens 359, the reflected image condensing lens 357, and the broadband fluorescent image condensing lens 358. Wideband bandpass filter 360 that selects the wideband, and a wideband that captures the autofluorescence image that has passed through the broadband bandpass filter 360 Transmitted through a narrowband bandpass filter 361 and a narrowband bandpass filter 361 that extract wavelengths from 430 nm to 530 nm from the autofluorescence image formed by the high-sensitivity imaging device 363 for optical images and the condensing lens 359 for narrowband fluorescence images. A high-sensitivity image sensor 364 for narrow-band fluorescence images that captures an autofluorescence image, a reflection image sensor 362 that captures a reflected image that has passed through a reflection lens condensing lens 357, and a control signal from a magnification control means 369 described later. Based on the high-sensitivity imaging device 363 for broadband fluorescent images, the high-sensitivity imaging device 364 for narrow-band fluorescent images, and the imaging device 362 for reflected images, the reading means 368 for reading out the image signals in the driving range and the reading means Based on the control signal from 368, the image signal output from the high-sensitivity image sensor 363 for broadband fluorescent image is converted into a digital value. The image signal output from the high-sensitivity image sensor 364 for narrowband fluorescent images is converted into a digital value based on the control signal from the AD converter 366 and the reading means 368 that converts the image data into image data and outputs it as image data. An AD converter 367 for outputting, an AD converter 365 for converting the image signal output from the imaging device for reflected image 362 into a digital value based on a control signal from the reading means 368, and outputting it as image data, an AD converter 366 Statistic for calculating a statistic based on image data output from the above and stored in a broadband fluorescent image memory 452 described later and image data output from the AD converter 367 and stored in a narrowband fluorescent image memory 453 described later Based on the statistics output from the calculation means 370 and the statistics calculation means 370, the imaging magnification system 356 and the normal image formation The magnification of the optical system 507 is determined, and a magnification control signal is output so that the magnification of the imaging optical system 356 and the normal image imaging optical system 507 becomes the magnification, and high sensitivity for broadband fluorescent images based on the magnification. The reading means 368 and 508 are controlled so as to determine the drive range in the image pickup device 363, the high-sensitivity image pickup device 364 for the narrow-band fluorescent image, the reflection image pickup device 362, and the normal image pickup device 503 and read out the image signal in the drive range. A magnification control means 369 for outputting a signal is provided. Note that the statistic calculation unit 370 includes a bit shift unit 371 that shifts the number of bits of image data to 8 bits or less.
[0095]
The image calculation unit 450 stores the broadband fluorescent image memory 452 that stores the image data of the broadband autofluorescence image output from the AD converter 366 and the image data of the narrowband autofluorescence image output from the AD converter 367. Narrowband fluorescent image memory 453, Reflected image memory 451 for storing the image data of the reflected image output from AD converter 365, Wideband autofluorescent image data and narrowband stored in broadband fluorescent image memory 452 A calculation corresponding to the ratio of the corresponding pixel values of the image data of the broadband autofluorescence image stored in the fluorescence image memory 453 is performed to calculate the calculated value of each pixel, and the color corresponding to the size of the calculated value Fluorescence image calculation means 455 that assigns information to generate and outputs a color image, and image data of the reflection image stored in the reflection image memory 451 Reflected image calculation means 454 that assigns luminance information according to the size and generates and outputs a luminance image, the color image generated by the fluorescence image calculation means 455 and the luminance image generated by the reflection image calculation means 454. An image synthesizing unit 456 for synthesizing and outputting as a synthesized image is provided.
[0096]
Next, the operation of the fluorescence endoscope in the above embodiment will be described. First, an operation in the case of displaying a composite image using autofluorescence images in two different wavelength bands will be described.
[0097]
Based on a signal from the control computer 250, the semiconductor laser power source 112 drives the pump light Lr from the GaN-based semiconductor laser 111. The pump light Lr passes through the pump light condensing lens 113, and the pump light guide. After being incident on 151b and guided to the distal end portion of the endoscope insertion portion 150, the living tissue 9 is irradiated from the illumination lens 153. The autofluorescence image from the living tissue 9 generated by the irradiation of the excitation light Lr is condensed by the condenser lens 155, passes through the excitation light cut filter 154, enters the tip of the image fiber 152, passes through the image fiber 152, The light enters the collimating lens 351. The excitation light cut filter 154 is a long pass filter that transmits all fluorescence having a wavelength of 420 nm or more. Since the wavelength of the excitation light Lr is 410 nm, the excitation light reflected by the living tissue 9 is cut by the excitation light cut filter 154. The autofluorescence image that has passed through the collimating lens 351 is reflected by the dichroic mirror 353 in the perpendicular direction. The autofluorescence image reflected by the dichroic mirror 353 is transmitted by the half mirror 354 with a transmittance of 50% and reflected with a reflectance of 50%. The autofluorescence image transmitted through the half mirror 354 reflects the narrowband fluorescence image mirror 355 in the perpendicular direction. The reflected image transmitted through the dichroic mirror 353, the autofluorescent image reflected from the half mirror 354, and the autofluorescent image reflected from the narrowband fluorescent image mirror 355 are all incident on the imaging optical system 356. At this time, the autofluorescence image first incident on the imaging optical system 356 is transmitted through the imaging optical system 356 at the same magnification. The autofluorescence image transmitted through the imaging optical system 356 at the same magnification is imaged by the condensing lens 358 for the broadband fluorescent image, and the autofluorescence image transmitted through the condensing lens 358 for the broadband fluorescence image is converted into the broadband bandpass filter 360. And is imaged by the high-sensitivity imaging device 363 for broadband fluorescent images. The autofluorescence image reflected by the narrowband fluorescence image mirror 355 is formed by the narrowband fluorescence condenser lens 359, passes through the narrowband bandpass filter 361, and is a highly sensitive image sensor 364 for narrowband fluorescence images. Is imaged.
[0098]
The autofluorescence images picked up by the high-sensitivity image pickup device 363 for the broadband fluorescent image and the high-sensitivity image pickup device 364 for the narrow-band fluorescent image are converted into image signals that are electric signals, and the image signals are read out by the control signals of the reading means 368, respectively. It is. The image signal output from the broadband fluorescent image high-sensitivity imaging device 363 is input to the AD converter 366 and digitized, and then stored in the broadband fluorescent image memory 452, and the narrow-band fluorescent image high-sensitivity imaging device. The image signal output from 364 is input to the AD converter 367, digitized, and stored in the narrowband fluorescent image memory 453.
[0099]
Here, after being stored in the broadband fluorescent image memory 452 and the narrowband fluorescent image memory 453 by the first self-fluorescent image capturing, the region of interest in the image data in the same manner as in the first embodiment. Image data is output to the statistic calculation means 370. Then, after the image data is bit-shifted to 8 bits or less by the bit shift means 371, the statistical value calculating means 370 calculates the average value as in the first embodiment, and then the average value is The magnification control means 369 outputs the magnification control means 369 to determine the magnification of the autofluorescence image and the normal image according to the average value, and applies the magnification to the imaging optical system 356 and the normal image imaging optical system 507 so as to obtain this magnification. Output a control signal.
[0100]
Then, the next autofluorescence image and reflection image are taken through the imaging optical system 356 controlled to an appropriate magnification by the magnification control signal of the magnification control means 369. Further, a driving range corresponding to the effective range is output from the magnification control unit 369 to the reading unit 368, and the reading unit 368 has a high-sensitivity imaging device 364 for narrowband fluorescent images and a broadband fluorescent image in the driving range corresponding to the effective range. The image data of the high-sensitivity image sensor 363 and the reflected image sensor 365 is read out. This effective range is an area to be displayed as an image, and may be set in advance or input by a predetermined input means (not shown). Further, when the narrow-band fluorescent image high-sensitivity image pickup device 364 and the wide-band fluorescent image high-sensitivity image pickup device 363 are, for example, a CCD, the reading unit 368 performs reading using the horizontal / vertical synchronization signal and the reference clock signal. The drive range is controlled according to the effective range by changing the horizontal / vertical synchronization signal and the reference clock frequency. The image data of the driving range corresponding to the effective range read by the reading unit 368 is stored in the narrowband fluorescent image memory 453, the broadband fluorescent image memory 452, and the reflected image memory 451.
[0101]
The narrow-band autofluorescence image in the effective range stored in the narrow-band fluorescence image memory 453 and the wide-band autofluorescence image in the effective range stored in the wide-band fluorescence image memory 452 An operation is performed according to the ratio of the pixel values of the image, color information is assigned to the calculated value, and an image signal having the color information is generated and output. On the other hand, the reflected image in the effective range stored in the reflected image memory 451 is assigned brightness information according to the size of the pixel value by the reflected image calculation means 454, and an image signal having the brightness information is generated and output. The Then, the color image signal output from the fluorescence image calculation unit 455 and the luminance image signal output from the reflection image calculation unit 454 are combined by the image combining unit 456, and a combined image is generated and output. The synthesized image output from the image synthesizing unit 456 is input to the monitor 600 after DA conversion by the video signal processing circuit 506, and the synthesized image in the effective range is displayed. It is possible to determine whether the tissue is a normal tissue or a diseased tissue based on the difference in color of the composite image.
[0102]
The operation of normal image display is the same as that in the first embodiment.
[0103]
A series of operations related to the combined image display operation and the normal image display operation are controlled by the control computer 250. The composite image display state and the normal image display state are switched by pressing the foot switch 2.
[0104]
According to the above-described fluorescence endoscope to which the fluorescence imaging apparatus according to the present invention is applied, the statistic calculating means 370 calculates the statistic of the image signal of the predetermined region of the fluorescent image, and the magnification control means 369 is based on the statistic. Since the sizes of the fluorescent image and the reflected image are determined by controlling the magnification of the imaging optical system 356, in addition to the effect of the first embodiment, the reflected image is made the size of the fluorescent image. The size can be made suitable, and even when image calculation is performed using a fluorescent image and a reflection image, appropriate inter-image calculation processing can be performed.
[0105]
In the first and second embodiments, the magnification control unit controls the magnification based on the statistic calculated by the statistic calculation unit. However, in actuality, the diagnosis is performed for all users. Easy, difficult to control to your preferred magnification. Accordingly, external input means such as a volume or a foot switch may be provided so that the user can appropriately control the magnification of the imaging optical system without providing the statistic calculation means. The user changes the enlargement / reduction based on the brightness or flicker of the observation image, switches the switch etc. to reduce when the observation image is dark or the flicker is large, and switches the switch etc. to enlarge when the observation is bright and the flicker is small. What is necessary is just to switch. Then, the image data may be read according to the effective range as in the first and second embodiments.
[0106]
In the first and second embodiments, the image corresponding to the image signal in the effective range is displayed on the monitor 600. In other words, the image displayed on the monitor 600 is controlled by the magnification control means. However, the display magnification may be controlled so that the size of the image displayed on the monitor 600 is always the same by providing display magnification control means. By controlling the magnification in this way, visibility can be ensured by enlarging the display even when the magnification is reduced by the magnification control means. The display image may be switched between a case where the display image is enlarged or reduced according to the magnification controlled by the magnification control means and a case where the display image is always displayed at the same size by a predetermined switch.
[0107]
In the first and second embodiments, the statistic is calculated by the statistic calculator based on the image data of the autofluorescence image. However, the statistic is calculated based on the image data of the reflected image. You may make it do.
[0108]
In the first and second embodiments, the statistic is calculated from the image data itself. However, the present invention is not limited to this, and the Y signal converted at the time of display (YIQ Y of the NTSC signal, Y of YCbCr) may be used. Alternatively, when the luminance information is assigned to the image signal of the reflected image, the statistic may be calculated from the luminance information.
[0109]
In the first and second embodiments described above, the reading unit reads the image data of only the effective range by controlling the driving range of each image sensor by the control signal of the magnification control unit. As another embodiment, after all the image data captured by each image sensor is read by the reading unit, the image is stored in the broadband fluorescent image memory, the narrow-band fluorescent image memory, the reflected image memory, and the normal image memory. When storing data, control may be performed so that only image data in the effective range is stored in each memory by a control signal from the magnification control means.
[0110]
In the first and second embodiments, the imaging optical system, the image sensor, the AD converter, and the reading unit are installed in the image processing unit. However, as another configuration, FIG. The imaging optical system 12, the image sensor 14, and the AD converter 15 may be arranged inside the endoscope insertion unit 10 as shown in FIG. In the embodiment shown in FIG. 4, the endoscope insertion unit 10 includes the condensing lens 11 that collects the autofluorescence image, the normal image, and the reflection image, the imaging optical system 12, the autofluorescence image, the normal image, and the reflection image. Is provided with a condensing lens 13, an image sensor 14, and an AD converter 15, and a control signal is output from the magnification control means 30 to the image forming optical system 12 and the image calculation unit 40 to perform image calculation. The broadband fluorescent image memory, the narrow-band fluorescent image memory, and the reflected image memory in the unit are controlled so as to store only the image data in the effective range in each memory by the control signal from the magnification control means 30 when storing the image data. Is done.
[0111]
Further, as shown in FIG. 5, the imaging optical system 52, the imaging device 54, the AD converter 55, and the reading unit 56 may be arranged inside the endoscope insertion unit 50. In the embodiment shown in FIG. 4, the endoscope insertion unit 50 includes the condensing lens 51 that collects the autofluorescence image, the normal image, and the reflection image, the imaging optical system 52, the autofluorescence image, the normal image, and the reflection image. Is provided with a condensing lens 53, an image sensor 54, an AD converter 55, and a reading means 56, and a control signal is output from the magnification control means 35 to the image forming optical system 52 and the reading means 56. Is done. The operation of each means is the same as in the first and second embodiments.
[0112]
In the first and second embodiments, the auto-fluorescent image sensor and the normal image sensor are provided, but they may be shared. Further, in the second embodiment, an image sensor for reflected images may be shared. In this case, imaging of each image may be switched in time series, or a self-fluorescent image, a normal image, and a reflected image may be separated and imaged by installing a mosaic filter on the surface of the image sensor. Good.
[0113]
Further, the magnification control means in the first and second embodiments may be incorporated in the control computer.
[0114]
Further, the imaging optical system in the first and second embodiments has a configuration in which an imaging optical system that forms a fluorescent image and a reflected image is separated from a normal image forming optical system that forms a normal image. However, a common configuration may be used.
[0115]
In the first and second embodiments, the normal image and the fluorescent image are matched with the fluorescent image in order to facilitate the association between the normal image and the fluorescent image. However, the normal image is fixed at a high magnification. You may leave as. In this case, a normal image with high resolution can be obtained. Further, the magnification of the normal image may be changed without changing the magnification of the normal image.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a first embodiment of a fluorescence endoscope to which a fluorescence imaging apparatus of the present invention is applied.
FIG. 2 is a schematic configuration diagram of a second embodiment of a fluorescence endoscope to which the fluorescence imaging apparatus of the present invention is applied.
FIG. 3 is an explanatory diagram of weighting calculation.
FIG. 4 is a partial schematic configuration diagram of another embodiment of the fluorescence image capturing apparatus of the present invention.
FIG. 5 is a partial schematic configuration diagram of another embodiment of the fluorescence image capturing apparatus of the present invention.
FIG. 6 is an explanatory diagram showing intensity distributions of fluorescence spectra of normal tissue and lesion tissue
[Explanation of symbols]
1, 3 Image signal processor
9 Living tissue
10, 50, 100, 150 Endoscope insertion part
11, 13, 51, 53 Condensing lens
12, 52 Imaging optical system
14, 54 Image sensor
15, 55 AD converter
20, 56 Reading means
30, 35 Magnification control means
40, 45 Image operation unit
101, 151 Light guide
101a, 151a White light guide
101b, 151b Excitation light guide
102, 152 Image fiber
103, 153 Illumination lens
104, 154 Excitation light cut filter
105, 155 Objective lens
110, 150 Lighting unit
111 GaN semiconductor laser
112 Power supply for semiconductor laser
113 Condensing lens for excitation light
114 White light source
115 Power source for white light source
116 Condensing lens for white light
117 Reference light source
118 Power source for reference light source
119 Condensing lens for reference light
200, 250 Control computer
300, 350 Image detection unit
301, 351 Collimating lens
302, 352 Movable mirror
303, 354 half mirror
304 Fluorescent image mirror
305, 356 Imaging optical system
306, 358 Condensing lens for broadband fluorescent image
307, 359 Narrow-band fluorescent image condenser lens
308, 360 Wideband bandpass filter
309, 361 Narrow band bandpass filter
310, 363 High-sensitivity image sensor for broadband fluorescent image
311 and 364 High-sensitivity image sensor for narrow-band fluorescent image
312, 313, 365, 366, 367, 504 AD converter
314, 368, 508 reading means
315, 370 Statistics calculation means
316, 369 Magnification control means
317, 371 Bit shift means
355 Mirror for narrow band fluorescent image
357 Condensing lens for reflection image
362 Image sensor for reflected image
400, 450 Image operation unit
401, 452 Broadband fluorescent image memory
402, 453 Narrow-band fluorescent image memory
403 image generation means
451 Memory for reflection image
454 Reflected image calculation means
455 Calculating means for fluorescent image
456 Image composition means
500 Display signal processing unit
501 Normal image mirror
502 Condensing lens for normal image
503 Image sensor for normal images
505 Normal image memory
506 Video signal processing means
507 Imaging optical system for normal images
600 monitors

Claims (31)

Irradiation means for guiding and irradiating excitation light to the measured part, and an imaging device for passing a fluorescence image based on the fluorescence image generated from the measured part by irradiation of the excitation light by the irradiating means through the imaging optical system In a fluorescence image capturing apparatus comprising: an image capturing unit that captures an image with a reading unit that reads out an image signal based on a fluorescent image captured by the image capturing unit;
Based on the images the signal of the fluorescent image captured by the imaging means includes a statistic calculation means for calculating a representative value representing the magnitude of said image signal,
The imaging means has magnification control means for determining the size of the fluorescent image by controlling the magnification of the imaging optical system based on the representative value ;
The fluorescence image capturing apparatus, wherein the statistic calculation means calculates a representative value of the image signal of the entire fluorescence image. Image processing means for performing predetermined image processing on the image signal read by the reading means;
2. The fluorescent image capturing apparatus according to claim 1, wherein the image processing means performs the image processing on the image signal in an effective range desired to be displayed as an image of the fluorescent image. Display means for displaying an observation image based on the image signal read by the reading means;
The display means, the image processing means the fluorescence imaging apparatus according to claim 2, characterized in that to display the observation image based on the image signal of Kieu effective range before subjected to image processing by. Fluorescence image before observation image based on the image signal of Kieu effective range, according to claim 3, characterized in that it has a display magnification control means for controlling the display magnification to be displayed at a fixed predetermined size Imaging device. The reading means, the fluorescent fluorescence imaging apparatus of claims 2, wherein 4 any one of claims that before Kieu is designed to read only the image signal of the effective range of the image. Irradiation means for guiding and irradiating excitation light and illumination light to the measurement target part, and a fluorescence image based on a fluorescence image generated from the measurement target part by irradiation of the excitation light by the irradiation means and irradiation of the illumination light Imaging means for picking up a normal image based on a normal image reflected from the measured part by an image pickup device through an imaging optical system, and reading means for reading out a fluorescent image picked up by the image pickup means and an image signal based on the normal image In a fluorescent imaging device comprising:
Based on the images the signal of the fluorescent image captured by the imaging means includes a statistic calculation means for calculating a representative value representing the magnitude of said image signal,
The fluorescence imaging apparatus characterized in that the imaging means has magnification control means for determining the sizes of the fluorescent image and the normal image by controlling the magnification of the imaging optical system based on the representative value. . Image processing means for performing predetermined image processing on the image signal read by the reading means;
Said image processing means, according to claim 6, wherein the one in which the ordinary the image signal of the image subjected to the image processing corresponding to the effective range and organic effective range to be displayed as an image of the fluorescence image Fluorescent imaging device. Display means for displaying an observation image based on the image signal read by the reading means;
Claims the display means, and characterized in that to display the observation image based on the image signal before Kieu effective range of the image processed the fluorescent image and the normal image by the image processing unit 8. The fluorescent image capturing device according to 7. Fluorescence image before observation image based on the image signal of Kieu effective range, it claim 8, wherein with the magnification control means for controlling the display magnification to be displayed at a fixed predetermined size Imaging device. The reading means, the fluorescent image and the normal fluorescence imaging apparatus of claims 7, wherein 9 any one of claims that before Kieu is designed to read only the image signal of the effective range of the image. Irradiation means for guiding and irradiating excitation light and reference light to the measured part, and irradiation of the fluorescence image and the reference light based on the fluorescence image generated from the measured part by irradiation of the excitation light by the irradiation means Imaging means for picking up a reflected image based on a reflected image reflected from the measured part by an image pickup device through an imaging optical system, and reading means for reading out an image signal based on the fluorescence image and the reflected image picked up by the imaging means In a fluorescent imaging device comprising:
Based on the images the signal of the fluorescence image or the reflected image captured by the imaging means includes a statistic calculation means for calculating a representative value representing the magnitude of said image signal,
The fluorescence imaging apparatus characterized in that the imaging means has magnification control means for determining the sizes of the fluorescent image and the reflected image by controlling the magnification of the imaging optical system based on the representative value. . Image processing means for performing predetermined image processing on the image signal read by the reading means;
Said image processing means, according to claim 11, wherein the one in which the image signal of the reflection image corresponding to the effective range and organic effective range to be displayed as an image of the fluorescence image subjected to the image processing Fluorescent imaging device. Display means for displaying an observation image based on the image signal read by the reading means;
Claims the display means, and characterized in that to display the observation image based on the image signal before Kieu effective range of the fluorescent image and the reflected image that is the image processed by said image processing means 12. The fluorescence image capturing device according to 12. Fluorescence image before observation image based on the image signal of Kieu effective range, according to claim 13, characterized in that it has a display magnification control means for controlling the display magnification to be displayed at a fixed predetermined size Imaging device. The reading means, the fluorescence image and the fluorescence image obtaining apparatus of claims 12 to be characterized before Kieu in which reading only the image signal of the effective area 14 to any one of claims of the reflected image. Irradiation means for guiding and irradiating excitation light, reference light and illumination light to the measurement target part, a fluorescence image based on a fluorescence image generated from the measurement target part by irradiation of the excitation light by the irradiation means, and the reference light An imaging device that captures a reflected image based on a reflected image reflected from the measurement target portion by irradiation of an image and a normal image based on a normal image reflected from the measurement target portion by irradiation of the illumination light through an imaging optical system. A fluorescence image imaging apparatus comprising: a reading means for reading out an image signal based on a fluorescence image, a reflection image, and a normal image captured by the imaging means;
Based on the images the signal of the fluorescence image or the reflected image captured by the imaging means includes a statistic calculation means for calculating a representative value representing the magnitude of said image signal,
The imaging unit includes a magnification control unit that determines the size of the fluorescent image, the reflected image, and the normal image by controlling the magnification of the imaging optical system based on the representative value. Fluorescence imaging device. Image processing means for performing predetermined image processing on the image signal read by the reading means;
Said image processing means, wherein the one in which the image signal of the reflected image and the normal image corresponding to the effective range and organic effective range to be displayed as an image of the fluorescence image subjected to the image processing The fluorescence imaging device according to claim 16. Display means for displaying an observation image based on the image signal read by the reading means;
Characterized in that said display means, the fluorescent image is an image processed by said image processing means, and displays the observation image based on the image signal before Kieu effective range of the reflection image and the normal image The fluorescence image capturing device according to claim 17. Fluorescence image before observation image based on the image signal of Kieu effective range, according to claim 18, characterized in that it has a display magnification control means for controlling the display magnification to be displayed at a fixed predetermined size Imaging device. The reading means, the fluorescent image, the reflected image and the normal image before Kieu effective range of the fluorescent image that is intended to read out the image signals only from the claims 17, wherein 19 to any one of claims Imaging device. Before SL statistic calculating means, the fluorescence image whole or the reflected image the whole of the image signal of the fluorescence imaging apparatus of claims 11, wherein 20 to any one of claims that calculates a representative value . Before SL statistic calculating means, the fluorescence imaging apparatus of claims 1, characterized in that calculates a representative value of the image signal of the region of interest of the fluorescence image 10 any one of claims. Previous SL statistic calculating means, the fluorescence image or the fluorescent image of the claims 11, characterized in that calculates a representative value of the image signal 20 to any one of claims ROI of the reflecting image apparatus. Claims wherein the statistic calculation means, characterized in that by the operation of the weighting according to the degree of interest in the range where the constant in said fluorescence image and calculates a representative value of the calculated image signals fluorescence imaging apparatus in claim 2 wherein.   The statistic calculation means calculates a representative value of the calculated image signal by performing an operation for weighting a predetermined range in the fluorescent image or the reflected image according to the degree of interest. 24. The fluorescence imaging apparatus according to claim 21 or 23, wherein The representative value of the image signal is at least one of a maximum value, a minimum value, an average value, a combination of a maximum value and a standard deviation, a combination of a minimum value and a standard deviation, and a combination of an average value and a standard deviation with respect to a luminance signal or a Y signal. 27. The magnification is reduced when any of the maximum value, the minimum value, and the average value of the statistic is small, and the magnification is increased when the statistic is large. Fluorescence imaging device. The reading means, before the fluorescence imaging apparatus of claim 5, 10, 15 or 20, wherein the controls the readout frequency depending on Kieu effective range. When the pixel data based on the image signal is indicated by the number of bits of 9 bits or more, it includes a bit shift means for performing a bit shift so that the data is indicated by the number of bits of the upper 8 bits or less,
28. The fluorescent image capturing apparatus according to claim 1, wherein the statistic calculation unit calculates the representative value based on the pixel data shifted by the bit shift.   29. The endoscope according to any one of claims 1 to 28, wherein a part or all of the irradiation unit, the imaging unit, and the reading unit are in the form of an endoscope having an insertion portion that is inserted into a living body. Fluorescent imaging device.   A part of the irradiation unit, the imaging unit, and the reading unit is disposed in the insertion unit, and a part of the irradiation unit, the imaging unit, and the reading unit other than the portion disposed in the insertion unit is a processor. 30. The structure according to claim 1, wherein the imaging system whose magnification is controlled by the magnification control means is disposed in the processor unit. The fluorescent image capturing device according to item.   A part of the irradiation unit, the imaging unit, and the reading unit is disposed in the insertion unit, and a part of the irradiation unit, the imaging unit, and the reading unit other than the portion disposed in the insertion unit is a processor. 30. The structure according to claim 1, wherein the imaging optical system controlled by the magnification control means is disposed in the insertion portion. Fluorescent imaging device.

Images